The invention is directed to a medical apparatus having an apparatus part which is motor-adjustable relative to a surface in a direction of at least one degree of freedom. A control means is provided for adjusting the apparatus part. A sensing card means is attachable to the surface and outputs a signal given presence of a subject in a region of the sensing card means. This signal is supplied to a control means which suppresses an adjustment of the apparatus part, given the presence of the signal. The term "subject" is intended to cover both life forms as well as articles.
In medical apparatus having an apparatus part which is adjustable relative to a surface--such as diagnosis or therapy apparatus--there is always a risk of injury for the operating personnel and also potentially for the patient since their bodies, particularly their extremities, can be clamped between the adjustable apparatus part and the surface. There is also the risk of damage to the apparatus when a foreign body is situated between the adjustable apparatus part and the surface. Efforts have thus been undertaken to suppress the risk of injury for the operating personnel and for the patient, as well as to suppress the risk of damage to the apparatus. For example, markings as well as sensing panels or cards to be applied to the respective surfaces are known as solutions to reduce these risks (DE-AS 21 49 240, German Patent 21 48 760 and German Published Application 38 11 380, all incorporated herein by reference). Markings, however, are only optical indications that are not always observed. Sensing cards can only represent a compromise in terms of their size and arrangement on the surface. First, there is the possibility of covering the entire endangered region with the consequence that, for example, disturbing interruptions or, respectively, inhibitions of the apparatus movement occur as a consequence of a person stepping on the sensing panel or card means without a risk to the person being actually established. If this disadvantage is to be avoided, on the other hand there is the possibility of making the sensing panel or card smaller, with the consequence that the entire endangered area is no longer protected to an adequate degree.
An x-ray apparatus disclosed in DE-AS 21 49 240 represents an improvement in that a plurality of sensing panels or card means allocated to individual risk zones is provided, these only taking affect when the adjustable apparatus part has approached the corresponding risk zone beyond a defined degree (the position of the adjustable apparatus part is monitored with the assistance of position-dependent switches) and the respectively desired apparatus motion would effect a further approach of the adjustable apparatus part to the risk zone. Here, too, however, there is the risk of unnecessary interruptions or inhibitions of apparatus movements, which can again only be avoided by making the circuit card allocated to the respective risk zone smaller, with the consequence that an adequate protection is then no longer guaranteed under all circumstances.